Azo dyestuffs



bearing the groupin p-position to the 'N=N-.group; R1 means hydrogenor an organic radical and R2 an organic-radical containing a 'sulfonic acidgroup atom; 12 standsior the "numbersone ortwo- 5l')"ucts thereof. v

ployed the 1-amino-8 hydroxynaphthalene sul-" fonic acids which are capable ofycoupling twic Patented Febt13, 1940 2,190,173 l Azo DYESTUFFS,

Helmut Kleiner, .Qologne-Mulheim; and Detl ei',

Delfs and Otto Bayer;L'eyerkusen- Wiesdorf, Germany, assignors to General Aniline& Film Corporation,acorporationoif'Delaware" a Q l The present invention relates to new azo dyestuffs and ;to a process; of preparing the same;

more particularly it relates to azo dyestufis of the Lgeneral formula e jinfthis general, formula A-N='N--pstands for i the radical of a-monodiazo compound, i .1 q y 1 for the radical of a tetrazo compound derived from a diaminodiaryl and C for an aromatic radical connected via a sulfur Our new dyestufisrcan be obtained by coupling in acid solution a tetrazotized diaminodiaryl with a -amino-8-hydroxynaphtha1ene I sulfonic acid capableof coupling twice, and combining the in: "termediate thus obtained with one mol of a monodiazo compound and one mol of an amine which couples in p-position and the amino group of which bears the radicals R1 and Rzdefined above. 1 The sulfonic acid group connected via a sulfur 'iatom, which is contained in the radical Ramay after the formation of the dyealso be'introduced stufi. I

As initial components (designated Am the above formula) may be used e. g. the amino com- 'pounds of the benzene series and their sulf onic or carboxylic acids, such as aniline, the aniline ,amirio, acetoamino and nitro substitution prodsuch as l-amino-8 hydroxynaphthalene=3,6-di

sulfonic acid; '1 amino-8-hydroxynaphthalene-1 eifi-disulfonic acid, I-aminQ-S-hydrQXYnaPhtha tinge'.".,The dyestuffs are dyeing leather and vegetableffibers which materials they generally dye in black shades. dyeingson'xyelvet leath As second components are emka ine byisodium carbonate. If in a testporj benzidine, its substitution products as e. g. the alkyl,jgalkoxy,;halogen substitution products and; the sulfonic acids thereof are used. The final lene isulfonic' acid. As tetrazo' components UNITED suresPATENT) ems" C mponents amines capable of coupling e p-position to the group 12, w 10, arelamines oi the benaene and naphthalene series; theymayfurjtheribe substituted in thefnulcleus by a1ky1, alkoxy, halogen and the .amino group,v

'I'hesefamines which; contain in thefr'adical R2 the sulf onicacid group connected vial a sulfur atom are obtainable by causinga corresponding amine which contains in the. radical R2 a reactive" grcup as e.-'Ig.j-halogento react with a thiosulfat'ew f or amercaptocompound. .In -thesame manner thesulfonic; acid group-connected viaua sulfur atomcan also: be introduced into the Rzfradical after the jformation or the dyestufi. R1 "in these I amines may stand e; 'g. for hydrogen, alkyl, hy-

dro xyalkyl, halogenalkyl, cycloalkyl and aralkyl. f

solubility in coldwater. Theyfdissolvelin 'water in general with bluish-black coloration andin' concentrate "sulfuric acid The V er ,arehdistinguishedby the desired-bluish tinge: v p

The following examples illustrate the inven- 351 tion, without, howeyergrestricting it thereto, the partsbeing by weight. i r

V 1 Eardmple l usual manner and combined'with 341 parts of the monosodium salt of the l-amino-S-hydroxynaphthalene=3,6- disulfonio acid in mineral acid solustirring well, antaqueous sodium carbonate solu the coupling 'with a more bluish pecially suited 'for i 30 tiongWAiter finishing the reaction' 93" parts of 5 aniline are diaz'otized' in the us'ualtinanner and sulfonic acids, the aniline carboxylic acids, the na ded;to th Then, iwhilehfioling, a d amino} diphenyl sulfonic acids and the halogen,

tion, taken therefrom, diazobenzene can no longer 18 i parts {of benzidine arefldiazotized in the addedt Aftersome -hoursstirrina the dyeetuiiob-{ 5 tained,which has in the free state the constitution: I I

is separated by adding salt;: It dyes cotton deep greenish black'shades. Also on leather it yields ,valuable black shades.

Especially the dyeings on velvet-leather are distinguished by the very desiredbluish-black shade. If the sodium N-butyl-anilinoethane-thiosulfate is replaced by a compoundoi the constitution a dyestufi is obtained which dyes the vegetable fiber and leather somewhat clearer and somewhat Hogs no new more bluish shades. If finstead of benzidine o-tolidine is used dyestuffs-of-similar properties are obtained. l v

I I Example" 2 I I 184 parts of benzidine are tetrazoti'zed and combined with 341 parts of the monosodiumsalt of the 1-amino-8-naphth01-3,6-disulfonic acid in mineral acid solution. Then an aqueous solution of diazobenzene-p-sulfonicacid, prepared from 17 3 parts of aniline-p-sulfonic acid is added and, while stirring andcoolingQthe mixture is rendered alkalineby sodium carbonate.

fate dissolved in water, are added. After stirring for some hours the dyestufi liquor is concentrated by evaporation and the dyestuff having in the free state the constitution Ho; scan" I is separatedby adding mineral acid and salt. 1 It dyes cotton and leather in" deep black shades.

Compared with the dyestuff of Example 11it possesses an even better solubility'and a somewhat redder shadef I V Similar dyestufisare obtained, if the butyl radical, of the sodium N-butyl-anilinoethane-thio i is is r a d b heme e h group;

I When all I vdia'z obenzene -p-sulfoioiti acid has disappeared, 311 I parts of sodium N-butyl-anilinoethane-thiosule 1 if it is replaced by the benzyl radical the shades shift somewhat to the greenish side.

omomssosn Ermmple 3 H The dyestufr intermediate isobtained as described in Example 1. As soon as diazobenzene can no longer be detected, 299

parts of sodium -(N-methyl-anilino)-c-hydroxy-propanethiosulfate dissolved in water are added. When the formation of the dyestufi is complete the reaction product having in the free state the constitution omonomssom is separated by adding salt. It dyes leather and cotton in deep black shades, which differ from II those of Example 1 by their bluer shade.

Example 4 t 184. parts of benzidine are tetrazotiaed in the usual-manner and combined with 341 parts of I the monosodium salt of the 1-amino-8-hydroxynaphthalene-3.6-disu'lfonic acid in mineral acid solution. When the coupling is complete 249 parts of the 1-aminodiphenyl-2-sulfonic acid are diazotized and added, and while cooling and stirring well, an aqueous sodium carbonate solution is added drop by drop, until the couplingliquor shows distinctly a reaction alkaline by sodium carbonate. .When no diazo compound canbedetected any longer an aqueous solution of 311 parts of sodium N-butylanilinoethane-thiosulfate is added. After stirring for some hours the trisazo dy'estufi having in the free state the constitution is separated by adding salt. It dyes wool in greyish-black shades; the black dyeings on leather are somewhat clearer and greener than those with the dyestufi of Example 2.

greenish-grey shades, cotton and viscose in Example 5 p 184 parts of benzidine are" tetrazotized and combined with 341 parts of the monosodium salt of the 1-amino-B-hydroxynaphthalene:3,6-disu1- fonic acid in acid solution. If uncoupled 1-a1nino-' 8-hydroxynaphthalene-3,6-disulfonic acid can no longer be detected an aqueous solution of diazobenzenel-sulfonio acid, obtained by diazotizing ethane-thiosulfate dissolved in 4000 parts of water are added. When after stirring for some hours without cooling the formation of the-trisazo dyestufi is finished, the liquor isweakly' acidified and the dyestuff havingin the free state the constitution Hos-G Q Hols Example 6 344 parts of benzidine-o.o-disulfonic acid are dissolved in about 2000 parts of hot water containing the requisite quantity of alkali, and when cold parts of sodium nitrite dissolved .in about 2000 parts of water are added. The mixture is run. into 1600 parts of hydrochloric acid (sp. gr. 1.15) diluted with three times the quantity of water. After 5 hours the tetrazo compound is separated and combined in mineral acid solution with 341 parts of the mono-sodium salt of the 1-amino-8-hydroXynaphthalene-4.6-disulionic acid. When the coupling is complete an aqueous solution of diazobenzenel-sulfonic acid, obtained by diazotizing 173 parts of p-sulfanilic acid is added and the mixture rendered weakly alkaline by sodium carbonate while stirring. When all diazobenzene-l-sulfonic acid-has disappeared, 311 parts of sodium N-butylanilinoethane-thiosulfate dissolved in water are added. After stirring for some hours the dyestufi", which in the free state has the constitution A rat/awn). R,

' hy droxyalkylene-S.SO3H and n stands for one substitution products and the sulfonic acids wherein AN=N- stands for theradical of a monodiazo compound of the benzene series,

-N=N -B N- I-N stands for the radical of a tetrazo compound series; C stands for an aromatic radical of the benzene series bearing the r group in p.-position to the N=N- group, R1

stands for a radical of the group consisting of zOeHs hydrogen, alkyl, hydroxyalkyl, halogenalkyl, cycloalkyl, and aralkyl, R; stands for one of the group consisting of -alkylene-S.SO3H and of the numbers one or two. l

2. As new products azo dyestuffs of the general formula OH NH:

wherein A,N=N- stands for the radical of a monodiazo compound of the benzene series,

thereof, C bearing the group in p-position to the .-N=N- groupstands it for one of the group consisting of the benzene nucleus and its alkyl, alkoxy,"halogen and amino substitution products, Ristands for a radical of the group consisting of hydrogen, alkyl, hydroxyalkyl, .halogenalkyl, cycloalkyLand aralkyl, R2

derived from a diaminodiaryl of thebenzene stands for one of the group consisting of H --alkylene-S.SOsI-I and -hydroxyalkylene* S.SO3H and n stands for one of the numbers one and two.

'3'. As new products azodyestufis of the general hydroxya1ky1ene--S.SO:;H and n stands for one formula of the numbers one and two.

OH NH:

wherein AN=Nstands for the radical of a 4. As new product the azo dyestufi correspond- 10 monodiazo compound of the benzene series, R1 ing in its free state to the formula,

0 H NH2 CHLOE! HOaS 0311 stands for a radical of the group consisting of dyeing cotton and leather deep black shades. 20 hydrogen, alkyl, hydroxyalkyi, halogenalkyl, cy- HELMUT KLEINER.

cloalkyl and aralky], R2 stands for one of the DE'ILEF DELFS. group consisting of -a1ky1ene-S.SOsI-I- and OTTO BAYER. 

